Summary: In this pair of clips, one can find a useful synopsis of Noam Chomsky's theory of Universal Grammar (UG), which is the theory that the ability to learn grammar is hard-wired into the brain. The first clip is an animated video and part of the BBC and Open University’s A History of Ideas series. The second clip comes from Gene Searchinger's Human Language series. • To summarize, Chomsky was unconvinced by other thinkers, like John Locke, who argued that people are born blank slates. Instead, Chomsky argued that children learning to speak cannot possibly start as blank slates because they simply don't have enough information to perform many of the complex grammatical maneuvers he observed them making. According to Chomsky, our proverbial slates cannot be completely blank when we are born; we must be hard-wired with structures in our brains, or what he called language acquisition devices (LADs). The LAD is a hypothetical tool hardwired into the brain that helps children rapidly learn and understand language. • The existence of this language acquisition device means that humans are born with a grasp or an intuition of the rules of language; what they must still learn from their social environments is simply vocabulary. As evidence that a language acquisition device is a genetic endowment common to all people, Chomsky pointed to the fact that language is fundamentally similar across cultures. For instance, every language has something like a noun and a verb, a way to ask a question, and a system for making obligatory distinctions (e.g., singular and plural forms of words). As the narrator of the first clip observes, it would appear that "our slates have been written on before we emerge from the womb."